Distributor



, G. LOUIS DIS IBUTOR July 1929.

Filed June 7, 1926 INVE 5r 7 56 if 56 47 5/ 4 i BY p ATTO Patented July 30, 1929.

UNITED STATES PATENT OFFICE.

TERRENCE G. LOUIS, OF SPRINGFIELD, MASSACHUSETTS, ASSIGNOR T0 WICO ELEC- TRIC COMPANY, OF WEST SPRINGFIELD, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

DISTRIBUTOR.

Application filed June 7,

This invention relates to improvements in electrical make and break mechanism, such as distributors or the like, and more particularly. to improvements in contacts therefor.

The invention, while capable of other applications, is especially suitable for use in distributors and especially in distributors of the type, in which the distributor arm moves back and forth between a pair of contacts. The invention will be disclosed for illustrative purposes in connection with a distributor of this particular type.

The invention has for one object to provide a contact, which is not only simple in construction and inexpensive to manufacture but which is calculated to give reliable service without requiring attention or adjustment and to have a long useful life in service because it is adapted to be engaged by the distributor arm or other equivalent element in such a manner that wear between the contacting parts is reduced to a minimum.

The invention makes use of a coil spring as the essential element of the contact and I am aware that coil springs have been used for this purpose before, as shown in U. S. patent to Kaufman, No. 1,411,787, dated April 4, 1922. This invention is distinguished from that of said patent in that the coil spring is firmly held at both ends and is adapted to be engaged by the distributor arm, or equivalent member, at a location on its periphery between the ends of the spring. The distributor arm, moving in a plane at substantially right angles to the axis of the coil spring, engages the latter between its ends and, while said ends are firmly held, the portion intermediate the ends is free to be flexed by the distributor arm, whereby the latter can flex the spring and form a seat for itself in the yielding coil spring. This arrangement is characterized in that the spring does not vibrate when flexed, as in said patent where the free end of a spring is struck by a wiper which necessarily results in the spring vibrating many times before it finally comes to rest. In the present case, as the distributor arm moves away from the spring, the latter merely resumes the position occupied prior to its flexure without vibration.

The invention has for another object the provision of im roved means for connecting the flexible con uctor of the distributor arm to a magneto terminal or the like.

1926. Serial No. 114,178.

Other objects and advantages will appear in the following description and will be pointed out in the appended claims.

The invention will be disclosed for illustrative purposes with reference to the accompanying drawings, in which Fig. 1 is a front elevational view of a distributor embodying the improved contact of this invention;

Fig, 2 is an enlarged cross sectional view taken on the line 22 of Fig. 1 and showing the construction of the contact;

Fig. 3 is an enlarged sectional plan view taken on the line 33 of Fig. 1 and showing the contact when flexed by engagement with the distributor arm and Fig. 4 is a view showing the several pa rts of the contact in dissociated relation.

. Referring to these drawings; there has been shown, as a background or setting for this invention, a distributor of the type disclosed in the copending application for U. S. Letters Patent of Phelps Brown, Serial No. 114,212, filed June 7, 1926. This distributor includes a case 10 of insulating material having four contacts 0 c 0 and 0, arranged in spaced relation and in the order named, in a row across the up per part of the case. A distributor arm 11 is pivoted at 12 near the lower end of case 10 and is movable in a plane at right angles to the axes of, and between, the contacts 0 and c. A similar arm 11 is provided to cooperate with the contacts 0 and 0. The arm 11 has fixed thereto a cam follower 13 adapted to be held against a cam 14 by a spring 15. The cam 14 is fixed to a gear 16 which is mounted on a stud 17 and driven by a pinion 18 which is adapted to be driven by the drive shaft of a magneto.

The cam 14 is constructed to move arm 11 from the position shown to the right and into engagement with contact 0 and at the same time to move arm 11 to the left disengaging it from contact 0 prior to the engagementof arm 11 with contact 0". The cam later moves arm 11 to the left and arm 11 still further to the left so that arm 11 is disengaged from contact 0 and arm 11 is engaged with contact 0 Subsequently, cam 14 moves arm 11 still further to the left into engagement with contact c and moves arm 11 to the right out of engagement with contact 0 As cam 14 can tinues to turn arm 11 is mo vet]. to the right out of engagement with contact 0 and arm 11 is moved still further to the right into engagement with contact 0. The cam 14. is constructed to cause the arms 11 and 11 to dwell for an interval when engaged with each ofits contacts and to cause one arm to dwell in a position intermediate its contacts whilethe other arm dwells in engagement with one'of its contacts. The arms 11 and 11 may be otherwise operated andthe present invention is independent of the plan of operation described. V

The I magneto terminal is shown at 20. Arm 11 has a conducting tip comprising a section of a coil spring 21 which is slipped over and embracesthe upper end of its arm. Integrally connected with spring section 21 is a second similar but longer spring section 22 which passes through an opening in arm 11 and has its other end held between the semicircular embracing ends 23of apair of conducting cross bars 24 which are fixed by a nut 25 to the magneto terminal 20. The section 22 forms a flexible connect-ion between the conducting tip 21 and the magneto terminal 20 and hasslack enough to permit tree movement of arm 11 throughout the desired range.

the ends of the spring and yet permit fleXure thereof in a direction at right angles to its axis at points intermediate such ends. As shown, a spool like support is providedavhich V is connected by a screw 31 to a terminal plate 32, embedded in case 10 and leading to a socket 33 inthe latter for connection to a distributor wire, such as '34:. This spool like supporting structure maybe madein various ways to accomplishthe stated purpose.

An example of one simple way of making up the spool is shown in the drawings. A thin washer 35, slightly larger than the outside diameter of spring 30 is first slipped on screw 31. followed by a somewhat thicker washer 36 of a diameter such as to fit within the convolutions of spring 30. A spacing sleeve 37, ofa diameter considerably less'than the internal diameter of spring 30, is next slipped upon screw 31. Then spring 30 is slipped over the sleeve 37 and washer 36 until one end engages the washer 35. The spring is then compressed enough to allow a second washer 36, followed by a second washer 35, to be slipped over the end of the screw 31. With the parts thus assembled on the screw, the free end of the latter is threaded into the terminal plate 32 and tightened up until each pair of washers is brought into contiguous relation and the smaller washers 36 are brought into contiguous relation with the ends of sleeve 37 The spring 30 is thus placed under the requisite degree of tension. The assembled supporting structure and contact then appears as shown in Fig. 2.

In operation, the distributor arm, or'lother equivalent element, is moved back and forth between the contacts in the described, or any other suitable manner, to alternately engage the springs of each pair of contacts, which is associated therewith. This arm, however, is preferably not moved merely into engagement with a contact spring 30 but is moved sufiiciently beyond the point ofbare engagement so as to flex spring 30 in the manner shown in Fig. 3. As there shown, the cylindrical conducting 'tip 21 forms for itself a seat in the sprin 30. The latter yields readily to the arm and yet at the same time the tendency of spring 30 to resume'its normal position causes it to hug a substantial part of the periphery of tip 21. A'bare engagement of these two cylindrical parts would result in point contact while by causing the arm'to flex spring 30, a substantial area of contact'be tween the engaging parts results.

7 An important feature of the contact construction is that it'allo'ws, by its yieldability, a'certain amount of overtravel of arm 11' and this is important. for reasonsother than that just pointed out above.

The arm and its actuating cam would have to be nicely constructed to insure proper engagement with the contacts if the latter were rigid.

Moreover, proper engagement couldnot be maintained after the parts became worn. Yielding of some sort between'th'e engaging "parts isthus a practical necessity and the tention being required to secure the result.

In addition, and as pointed out in said copending application, the arms may be so operated (with dwell intervals in the manner above described) as to entirely avoid sparking between the arms and contacts. "With this destructive agency eliminated, the contact is adapted for a long useful life'because the engaging parts are never under heavy strainsand because shocks and impacts are eliminated from the engagement.

The features of the distributor relating to the manner of operating the distributor arms and'the c'onstructionof the conducting tip for said arms and the flexible conductor therefor were invented by Phelps Brown, of Springfield, Massachusetts, prior to the filing of this application and said features form the subject matter of the above identified copending application.

The invention has been disclosed herein, in an embodiment at present preferred, for illustrative purposes, but the scope of the invention is defined by the appended claims rather than by the foregoing description.

Vhat I claim is:

1. In a distributor, an oscillating distributor arm, a pair of contacts between which said arm is movable, a conducting tip for said arm consisting of a coil spring section encompassing the free end of said arm and a second coil spring section connected to said first named section, a fixed electrical terminal, and a pair of conductors having opposed and substantially semi-circular ends between which the free end of said second coil spring section is clamped, said conductors being stationarily supported and electrically connected to said terminal.

2. In combination, a pair of contacts, each comprising a coil spring and means for supporting the same at opposite ends with freedom for fiexure intern'lediate said ends in directions at substantially right angles to the axis of the spring, said springs being supported with their axes in parallel relation, and an arm mounted for swinging movement in a plane at right angles to said axes and movable to alternately engage said springs, said arm adapted to engage theperiphery of each spring intermediate its ends and to flex the spring sufliciently so that the arm becomes partially embedded in the spring.

3. In a circuit controller, a contact comprising a coil spring and means for supporting the same at longitudinally spaced points with freedom for flexure intermediate said points in directions at substantially right angles to the axis of the spring, and a cooperating contact arm, said arm and contact being relatively movable and the arm being disposed at substantially right angles to the axis of said spring so as to engage the latter on relative movement at a point intermediate its points of support and flex the spring laterally so that the arm becomes partially embedded therein.

In testimony whereof I have atlixed my signature.

TERRENCE G. LOUIS. 

